Evolution and metabolic significance of the urea cycle in photosynthetic diatoms

  title={Evolution and metabolic significance of the urea cycle in photosynthetic diatoms},
  author={Andrew Ellis Allen and Christopher L. Dupont and Miroslav Oborn{\'i}k and Ale{\vs} Hor{\'a}k and Adriano Nunes‐Nesi and John P. McCrow and Hong Zheng and Daniel A. Johnson and Hanhua Hu and Alisdair Robert Fernie and Chris Bowler},
Diatoms dominate the biomass of phytoplankton in nutrient-rich conditions and form the basis of some of the world’s most productive marine food webs. The diatom nuclear genome contains genes with bacterial and plastid origins as well as genes of the secondary endosymbiotic host (the exosymbiont), yet little is known about the relative contribution of each gene group to diatom metabolism. Here we show that the exosymbiont-derived ornithine-urea cycle, which is similar to that of metazoans but is… 

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